1. Field of the Invention
The present invention relates to an inspection apparatus used for inspecting the electrical characteristics of an object to be measured.
2. Background Art
It is known practice to inspect the electrical characteristics of a heated object to be measured by bringing a contact probe into contact with the object. The contact probe is typically secured to an insulating substrate. Japanese Laid-Open Patent Publication No. 2012-47503 discloses a technique for varying the temperature of a probe substrate (or insulating substrate) in accordance with changes in the temperature of the object to be measured. This technique directly heats the insulating substrate to the desired temperature. Published Japanese Translation of PCT Application No. 2012-503304 discloses a technique for supplying a temperature-controlled gas flow to within an inspection apparatus so as to regulate the temperature of the insulating substrate to the desired temperature.
The technique disclosed in the above Patent Publication No. 2012-47503 is disadvantageous in that the insulating substrate may expand or warp due to the heat applied to the substrate. The expansion or warpage of the insulating substrate results in displacement of the contact probe attached to the insulating substrate, making it impossible to bring the contact probe into contact with the desired point on the object to be measured and press the contact probe against the object with the desired pressure. Further, heat is transferred from the heated object to be measured to the insulating substrate through the contact probe, thereby causing the insulating substrate to expand or warp.
The technique disclosed in the above Published Japanese Translation of PCT Application No. 2012-503304, on the other hand, can be used to maintain the insulating substrate at, e.g., approximately room temperature. However; a complicated apparatus and considerable electric energy are required to supply a temperature-controlled gas flow.